The present invention generally relates to an electrode structure, and more particularly, to an electrode structure with white balance adjustment for a plasma display panel (PDP).
Due to the rapid development of multimedia applications, the user has a great demand for entertainment equipment. Conventionally, the cathode ray tube (CRT) display, which is a type of monitor, is commonly used. However, the cathode ray tube display does not meet the needs of multimedia technology because it occupies a large space. Therefore, many flat panel display techniques such as liquid crystal display (LCD) and plasma display panel (PDP) have been recently developed. These display techniques can manufacture a thin, light, short and small monitor, and thus these techniques are becoming the mainstream technology for the future. Of these techniques, the plasma display panel (PDP) is attracting attention in the field of displays as a full-color display apparatus having a large size display area and is especially popularly utilized in large size televisions or outdoor display panels. FIG. 1 shows an electrode structure of the plasma display panel according to the prior art.
An electrode structure includes a common electrode 100, a scan electrode 102 and barrier ribs 104, of which the common electrode 100 includes a narrow bus electrode 106 and a broad transparent electrode 108. The transparent electrode 108 has a constant width and contacts the bus electrode 106.
Due to an electrode structure with three primary colors, blue, red and green, the plasma display panel has varying luminance with respect to the three primary colors. Thus, the constant width 110 of the transparent electrode 108 results in a greater luminous difference between the three primary colors at a high brightness. Therefore, the display colors are imbalanced and impure.
The output gain of image signals is adjusted to correct the white balance of the plasma display panel. However, such an adjustment of output gain also simultaneously reduces the gray scale of the lower brightness, such as blue, so that the range of the gray scale is severely reduced causing a poor display. Additionally, the adjustment of the output gain of the image signals is still unable to control the luminance of the three primary colors by discharging simultaneously.
Consequently, how to improve a poor white balance due to inconsistency of the display is an important problem and is currently a main issue for plasma display panel manufacturers.
One object of the present invention is to utilize an electrode structure with white balance adjustment for a plasma display panel (PDP) to modify the differing luminance of the three primary colors in the luminant units by separating a transparent electrode from the main line of the comb electrode.
Another object of the present invention is to utilize an electrode structure with white balance adjustment for a plasma display panel (PDP) to adapt the differing luminance of the three primary colors in the ruminant units to obtain a preferred white balance by a plurality of steps of the transparent electrodes.
Still another object of the present invention is to utilize an electrode structure with white balance adjustment for a plasma display panel (PDP) to optimize the luminance and efficiency of the luminant units by reducing properly the step width of transparent electrodes.
According to the above objects, the present invention sets forth an electrode structure with white balance adjustment for a plasma display panel (PDP). The electrode is formed on the substrate and electrically couples with a signal generator to control the gas discharge of luminant units in a row. The electrode includes a comb electrode, a first transparent electrode and a second transparent electrode.
The comb electrode coupled to the signal generator has a main line and a plurality of branches outwardly perpendicular to the main line. The first transparent electrode is parallel to the main line of the comb electrode and electrically coupled to the branches of the comb electrode. The first transparent electrode has a plurality of steps having a variant width. The second transparent electrode is parallel to the main line of the comb electrode and electrically connects to the end portion of the branches of the comb electrode.
Specifically, the first transparent electrode is separated from the second transparent electrode and the comb electrode, respectively, to increase the flexibility of the transparent electrode by modifying the profile of the transparent electrode. For example, the profile of the first transparent along the branches of the comb electrode comprises a stepped or slanted profile. The width of the first transparent electrode is adjusted for the three primary colors of the luminant units to control the visible light through the first transparent electrode to acquire a preferred white balance.
More importantly, since the width of the transparent electrode corresponds to the three ruminant units, also known as a pixel, the plasma display panel can precisely adjust the display color of the ruminant units by controlling the brightness of the three luminant units for an improvement of the white balance.
In summary, the present invention provides an electrode structure with white balance adjustment to modify the differing luminance among the three primary colors in the ruminant units by separating the transparent electrode from the main line of the comb electrode. Further, using step and strip transparent electrodes combined with the comb electrode allows adjustment of the differing luminance of the three primary colors in the luminant units for a preferred white balance.